Gladiator movies used to be nicknamed “sword and sandal epics.” But thanks to “Spartacus” — the outrageous new TV series on Starz — they could just as easily be called “sex and violence” epics.

The new season begins next month and fans won’t have to wait long for beheadings, throat slashings, copious amounts of blood, full-frontal nudity and countless sex scenes between masters and slaves, men and women, and several other combinations as well.

And that’s just the first episode.

“That’s nothing, mate,” says Lucy Lawless, the New Zealander who shot to fame as Xena and also had a major role on the acclaimed “Battlestar Galactica” reboot. “I’m forbidding my parents to watch.”

Really?

“Well, I’d like to — but unfortunately they’re grownups, and I can’t really tell them what to do,” says Lawless, who plays Lucretia, the wife of the owner of the gladiator school. “But I cringe to think of them watching the prequel.”

If her parents do watch, they won’t be alone.

The first season of “Spartacus” was a phenomenon. It told the story of the origin of the gladiator who became famous in the arena and then led a slave rebellion against Rome.

It debuted to more than 500,000 viewers — and then grew. The season finale was seen by more than 1.2 million viewers. It is a rare TV series that more than doubles its debut audience the way “Spartacus” has.

Apparently, word got out about a TV series that combined the graphic novel coolness of the movie “300” with equally graphic adult content.

With the mind-blowing content seen every week, does Starz even have a Standards & Practices department?

“Not the way a network does,” laughs creator Stephen S. DeKnight, who credits Joss Whedon of “Buffy The Vampire Slayer” fame for giving him his big break.

“We got a note on episode eight with Segovax [Mike Edward], the very well-endowed gladiator,” DeKnight says. “There was a shot in the bathhouse where Spartacus is sitting down and Segovax comes up to talk to him. And the way it was framed, you saw Segovax’s endowment before you saw Segovax. And they thought that was a bit much.”

Lawless wasn’t feeling so bold now that her daughter, Daisy Lawless, is also working on the set.

“I say, ‘Turn your back for the next 20 minutes, Daisy,’ ” Lawless says. “It must be really weird to have your mother engage in some shocking behavior.”

Surprisingly, that shocking behavior hasn’t sparked an outcry, though “Spartacus” is even more violent than the other breakout show of the moment, the brutal zombie fest “The Walking Dead.”

“Really, I can count on one hand the number of times Starz asked us to snip something out. And usually it was a giant shot of a penis or Spartacus ripping somebody’s throat out with his teeth,” he laughs. “They give us incredible latitude to tell the story the way we want to.

“I’m hoping people realize it’s not just sex and violence, and we’re telling a story. I know Starz was expecting to get a bit of an outcry, but it just never happened.”

TV historian Tim Brooks says being on pay cable helps tremendously.

“Frontal nudity and extreme violence seem to be the last frontier of specialty channels seeking attention from the mostly upscale viewers who will pay extra for the thrill,” says Brooks, the co-author of “The Complete Directory to Primetime Network and Cable TV Shows.”

“You recall that Showtime made a mark some years ago with ‘Queer as Folk,’ which was pretty racy for its time,” says Brooks.

“The violence and nudity is generally contained within a serious narrative about historical subjects, like ‘The Tudors.’ It’s hard to attack that without seeming prudish.”